How Jupiter's Red Spot Stays Great

Scientific American

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Jupiter’s Great Red Spot. It’s one of the most familiar sites in our solar system. It’s also one of the most mysterious. Because, based on most calculations, this flashy display of swirling gases should be long gone. Now, scientists think they know the secret to the storm’s endurance. Which they reveal at a meeting of the American Physical Society’s Division of Fluid Dynamics in Pittsburgh. [Pedram Hassanzadeh and Philip Marcus, On the Unexpected Longevity of the Great Red Spot, Oceanic Eddies, and other Baroclinic Vortices]

The Great Red Spot is like a humongous hurricane. But one that’s raged for hundreds of years. Most models find that turbulence and heat loss should have bled away the spot’s energy. And a pair of nearby jet streams, which flow in opposite directions, should have slowed its spin. So how is it still there?

In the latest analysis, researchers built a 3D model of the Great Red Spot and really gave all three dimensions their due. They discovered that as the spot’s horizontal winds are depleted, a vertical flow of gas from above and below keeps feeding it energy. And a circular flow sucks energy from those jet streams and diverts it into the storm. All of which keeps the red spot great, by Jove.

--Karen Hopkin

[The above text is a transcript of this podcast.]

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